1. Field of the Invention
This invention relates to a method and apparatus for controlling a cogeneration system, particularly to a method and apparatus for controlling operation of a cogeneration system that prevents condensate water from being accumulated.
2. Description of the Related Art
In recent years, cogeneration systems have been developed that are equipped with an internal combustion engine-driven generator for installation in an AC power supply line between a commercial power network and an electrical load for supplying power to the load in interconnection with the power network and also for supplying hot water or the like heated using exhaust heat from the engine to a thermal load. Such a cogeneration system is taught, for example, by Japanese Laid-Open Patent Application No. Hei 8-4586.
In such a cogeneration system, when temperature of coolant of the engine is low in a heat exchanger that exchanges heat with the coolant with exhaust heat to warm up, moisture in the exhaust gas may be condensed and accumulated (pooled) in the system. The accumulated condensate water reacts with components in the exhaust gas and it likely leads to corrosion of the heat exchanger.